A boot is a type of footwear that encases both the foot and a portion of the lower leg of a user. Boots are generally manufactured for a particular purpose or activity and therefore are designed to include characteristics consistent with the intended purpose. For example, a hiking boot is designed to support the ankle of a user while minimizing the overall weight. Likewise, a ski boot is designed to maximize a user's performance at a particular skiing activity.
Boots generally include a shell, a compression system, and a sole. The shell and compression system operate to encase and support the foot and lower leg of a user. Various well-known shell and compression systems are utilized to allow users to insert and remove their feet in an open boot configuration and compress the shell around the foot in a closed boot configuration. The sole of a boot is disposed on the bottom surface of the shell. The sole is generally composed of a rubber or plastic material. The sole may consist of a single piece or multiple blocks. The stiffness and/or weight characteristics of the sole have an affect on the overall performance of the boot.
The general activity of skiing comprises many subsets including but not limited to alpine touring, telemark, and downhill. Each subset of skiing generally corresponds to a unique system of specialized equipment. For example, the boot, ski, and binding systems used for telemark skiing are significantly different from those used for alpine touring. A skiing system may include standard types of boots, skis, and bindings. Each type of skiing also requires unique characteristics of a boot to achieve optimal performance. In addition, particular terrain and skier preference may require an even more specific set of performance characteristics. Boots for particular skiing activities must be compatible with the remainder of the system. For example, telemark skiing boots have generally been required to conform to the 75 mm standard to allow for compatibility with telemark type bindings.
One of the problems with existing boot systems is their limited adaptability to a variety of systems, activities and/or user preferences. Most conventional skiing boots can be adjusted with the compression system to provide different degrees of compression between the shell and user's foot. This adjustment can be used to control a variety of characteristics. However, certain boot performance characteristics such as binding compatibility, sole flex, torsion, and weight cannot be adjusted with the compression system.
Therefore, there is a need in the industry for a modular boot system that allows for multi-binding compatibility and the adjustment of certain sole related flexibility and weight characteristics without substantially affecting performance.